One area of difference is in the conditionals. I never use WHEN or UNLESS for value; only for effect. And, I never write NIL as one of the values returned by IF; I always condense the expression to AND or OR. That is, I freely use AND and OR to return non-boolean values; this is a practice some deprecate, and indeed, I'm surprised not to find it explicitly mentioned here.
I do like to write certain kinds of iteration as tail-recursions, but I always use local functions (LABELS) when doing that; there's no implementation I use regularly that doesn't do tail-call optimization on local calls.
Comments
A very useful document that I mostly agree with.
One area of difference is in the conditionals. I never use WHEN or UNLESS for value; only for effect. And, I never write NIL as one of the values returned by IF; I always condense the expression to AND or OR. That is, I freely use AND and OR to return non-boolean values; this is a practice some deprecate, and indeed, I'm surprised not to find it explicitly mentioned here.
I do like to write certain kinds of iteration as tail-recursions, but I always use local functions (LABELS) when doing that; there's no implementation I use regularly that doesn't do tail-call optimization on local calls.
Using AND and OR to return non-boolean values is one of the best, most useful parts of Common Lisp.